KR101363198B1 - Process for producing pentaerythritol mercaptocarboxylic acid ester, pentaerythritol mercaptocarboxylic acid ester obtained by the same, and use thereof - Google Patents

Abstract

When neither alkali metals nor alkaline earth metals are contained or at least one of them is contained, pentaerythritol and mercaptocarboxylic acid having a total content of 1.0% by weight or less are reacted to pentaerythritol mercaptocarboxylic acid. Prepare esters.

Description

The manufacturing method of pentaerythritol mercaptocarboxylic acid ester, the pentaerythritol mercaptocarboxylic acid ester obtained by this, and its use

This invention is a manufacturing method of pentaerythritol mercaptocarboxylic acid ester, the pentaerythritol mercaptocarboxylic acid ester obtained by this, the polymeric composition containing this pentaerythritol mercaptocarboxylic acid ester, and resin obtained from this polymeric composition, and The optical element and the lens which consist of this resin are related.

Since plastic lenses are lighter, less fragile, and can be dyed compared to inorganic lenses, plastic lenses have recently been widely used in optical elements such as spectacle lenses and camera lenses.

As the resin for plastic lenses, further high performance is required, and high refractive index, high pressure Abbe hydration, low specific gravity, high heat resistance, and the like have been demanded. Until now, various resin materials for lenses have been developed and used.

Especially, proposals regarding polyurethane resins are actively made, and the present inventors also make various proposals regarding plastic lenses using this polyurethane resin (see Patent Document 1, Patent Document 2, and Patent Document 3). ).

Among them, the resin obtained by reacting pentaerythritol mercaptocarboxylic acid ester with a polyiso (thio) cyanate compound as the most typical resin is colorless transparent, high refractive index low dispersion, and excellent plasticity with excellent impact, dyeability, processability, and the like. It is one of the most suitable resins.

Pentaerythritol mercaptocarboxylic acid ester is manufactured by the so-called direct esterification method which performs normal polyhydric alcohol and mercaptocarboxylic acid distilling off the by-product water in the presence of an esterification catalyst out of the system. (Refer patent document 4) )

Pentaerythritol which is a raw material of this ester compound is usually produced by condensing acetaldehyde and formaldehyde. The purity is usually about 90% by weight, containing various kinds of impurities. Especially, bispenta erythritol which is a formaldehyde 2-molecule condensate of pentaerythritol is mentioned. When this bispenta erythritol is contained more than 5 weight%, it is known that the release from a mold is difficult after completion | finish of superposition | polymerization with a polyisocyanate compound, or the problem which produces an air bubble in the obtained lens is known. (Patent document) 5, 6).

Patent Document 1: Japanese Patent Publication No. 60-199016

Patent Document 2: Japanese Patent Application Publication No. 60-217229

Patent Document 3: Japanese Patent Laid-Open No. 63-46213

Patent Document 4: Japanese Patent Publication No. 39-9071

Patent Document 5: Japanese Patent Application Publication No. 56-20530

Patent Document 6: Japanese Patent Application Laid-open No. Hei 10-120646

The pentaerythritol containing such bispentaerythritol can be made into 5 weight% or less of content of bispentaerythritol by the heat processing of 160 degreeC-200 degreeC, for example, with the pentaerythritol content of 98 weight% or more It is known that it can further refine | purify (refer patent document 5). However, also when using the pentaerythritol refine | purified in this way, the lens obtained by superposing | polymerizing the obtained pentaerythritol mercaptocarboxylic acid ester and a polyisocyanate compound may be cloudy, and the suppression was desired.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the above-mentioned subject, the present inventors discovered that the cause of the turbidity of a polyurethane-type lens was in the pentaerythritol mercaptocarboxylic acid ester which is a monomer. As a result of further investigation, surprisingly, when the pentaerythritol mercaptocarboxylic acid ester produced by using pentaerythritol having a total content of sodium and calcium in a specified amount or less as a raw material, the above problem was solved, and colorlessness in which cloudiness was suppressed was suppressed. It discovered that a transparent polyurethane-type lens was obtained and came to this invention. Moreover, when the content of the sum total of a specific metal is below a specific amount, it discovered that the same effect is acquired and came to this invention.

That is, the first invention of the present invention contains neither pentaerythritol nor mercaptocarboxylic acid whose content is 1.0% by weight or less in the case of containing neither alkali metal nor alkaline earth metal, or at least one of them. It relates to a method for producing pentaerythritol mercaptocarboxylic acid ester to be reacted.

Moreover, in this 2nd invention, when neither Na or Ca is contained, or when it contains one or both, the penta which reacts the pentaerythritol whose content is 1.0 weight% or less in total, and mercaptocarboxylic acid, is reacted. It relates to a method for producing erythritol mercaptocarboxylic acid ester.

In addition, in this third invention, none of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn When it does not contain or contains at least 1 type, it is related with the manufacturing method of the pentaerythritol mercaptocarboxylic acid ester which makes the pentaerythritol whose content is 1.0 weight% or less in total, and mercaptocarboxylic acid react.

Moreover, according to this invention, the pentaerythritol mercaptocarboxylic acid ester obtained by some of the manufacturing methods mentioned above can be provided.

Moreover, according to this invention, the polymeric composition which consists of said pentaerythritol mercaptocarboxylic acid ester and a polyiso (thio) cyanate compound can be provided.

Moreover, according to this invention, resin obtained by hardening | curing said polymeric composition can be provided.

Moreover, according to this invention, the optical element which consists of said resin can be provided.

Moreover, according to this invention, the lens which consists of said resin can be provided.

According to this invention, the pentaerythritol mercaptocarboxylic acid ester which is not cloudy can be obtained even if it reacts with a poly (iso) thiocyanate. As a result, it is possible to provide a colorless and transparent polyurethane lens having excellent optical properties in which cloudiness is suppressed.

Hereinafter, an embodiment of the present invention will be described.

In the manufacturing method of obtaining the pentaerythritol mercaptocarboxylic acid ester which concerns on this embodiment, when neither an alkali metal nor an alkaline earth metal is contained, or when it contains at least 1 type, the content is 1.0 weight% in total. The following pentaerythritol and mercaptocarboxylic acid are made to react.

Moreover, the manufacturing method which obtains the pentaerythritol mercaptocarboxylic acid ester which concerns on other embodiment contains neither Na and Ca, or when it contains one or both, the content is 1.0 weight% or less in total. It is made to react pentaerythritol and mercaptocarboxylic acid.

Moreover, the manufacturing method of obtaining pentaerythritol mercaptocarboxylic acid ester which concerns on other embodiment is Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ti, V, Cr, Mn, Fe, When none of Co, Ni, Cu, and Zn is contained, or at least one type thereof is contained, pentaerythritol having a content of 1.0% by weight or less in total and mercaptocarboxylic acid are reacted.

Pentaerythritol as a raw material of the ester compound used in the present embodiment can be specified by the content of bispentaerythritol and the total content of various metals such as alkali metals and alkaline earth metals.

In this embodiment, the pentaerythritol whose content of bispenta erythritol is 5.0 weight% or less, and content of various metals, such as an alkali metal and an alkaline earth metal, is 1.0 weight% or less in total is used optimally.

Here, when content of bispentaerythritol is 5.0 weight% or less, the polyurethane-type lens which is excellent in mold release property and does not produce a bubble can be obtained. The content of bispentaerythritol can be measured by gas chromatography, for example as in Patent Document 5, or can be measured by high performance liquid chromatography as in Patent Document 6.

You may reduce content of bispentaerythritol by employ | adopting a conventionally well-known method suitably, for example. For example, it may heat-process at 160 degreeC-200 degreeC like description of patent document 5, and may hydrolyze while heating and refluxing in nitrogen atmosphere like description of patent document 6. By applying these means suitably, the pentaerythritol whose content of bispenta erythritol is 5.0 weight% or less can be obtained.

Here, "the content is 1.0 weight% or less in total when it contains neither an alkali metal nor alkaline-earth metal, or contains at least 1 type" as pentaerythritol used in this embodiment. Any of alkali metals and alkaline earth metals, including no alkali metals, no alkali earth metals, and no alkali metals and no alkaline earth metals. When it contains only one, it means that the content is 1.0 weight% or less in total.

In addition, "the content is 1.0 weight% or less in total when it contains neither sodium and calcium, or at least 1 type" is the pentaerythritol used in this embodiment, and it does not contain sodium at all. If it does not contain any, contains no calcium at all, and contains neither sodium nor calcium at all, and if it contains either sodium and calcium, the content is 1.0 in total. It means below% by weight.

In addition, "Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn contains none, or And when it contains at least one of them, the content thereof is 1.0% by weight or less in total '' means pentaerythritol to be used in the present embodiment, including those containing no such metals at all, and adding one of these metals. When including a kind, it means that the content is 1.0 weight% or less in total.

When the content of alkali metal and alkaline earth metal is 1.0% by weight or less in total, the polyurethane lens obtained by polymerizing pentaerythritol mercaptocarboxylic acid ester and polyiso (thio) cyanate produced using the pentaerythritol It becomes a colorless and transparent polyurethane lens with reduced cloudiness. From the viewpoint of suppression of clouding, the content of alkali metal and alkaline earth metal of pentaerythritol used in the present embodiment is 1.0% by weight or less in total, preferably 0.5% by weight or less in total, and more preferably 0.2% in total. % Or less

Similarly, from the viewpoint of suppression of clouding, the content of sodium and calcium is 1.0% by weight or less in total, preferably 0.5% by weight or less in total, and more preferably 0.2% by weight or less in total.

Similarly, from the viewpoint of suppression of cloudiness, Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn Content of various metal elements is 1.0 weight% or less in total, Preferably it is 0.5 weight% or less in total, More preferably, it is 0.2 weight% or less in total.

The measuring method of content of a metal element is as follows. About light metals, such as Na, pentaerythritol is made into aqueous solution, and then quantified by ion chromatograph method. As for the heavy metals in general, the pentaerythritol is dissolved in a color developing solution after incineration, and then colored, and the content is quantified by an atomic absorption method for measuring absorbance, a plasma luminescence analyzer, or the like. The content of sodium and calcium and the content of the various metals, including alkali metals and alkaline earth metals, may be reduced to 1.0% by weight by reducing the metal components. For example, it can also be reduced by acid treatment with hydrochloric acid, sulfuric acid, or the like, and can be reduced by recrystallization with an aqueous system.

Moreover, mercaptocarboxylic acid which is one raw material is a compound which has 1 or more mercapto group and 1 or more carboxyl group in 1 molecule, and is not specifically limited in quality, A normal industrial chemical is used suitably. Specifically, thioglycolic acid, thio lactic acid, 3-mercaptopropionic acid, thiomalic acid, thiosalicylic acid, etc. are mentioned, for example, It is not limited to these exemplary compounds. In addition, these may be made to react two or more types with pentaerythritol alone.

As an esterification catalyst normally used in order to make pentaerythritol and mercaptocarboxylic acid react, For example, mineral acids, such as a sulfuric acid, hydrochloric acid, phosphoric acid, and alumina, and p-toluenesulfonic acid, benzenesulfonic acid, methanesulfuric acid Acid catalysts represented by organic acids such as phonic acid, trichloroacetic acid and dibutyltin dioxide are preferably used.

In the preparation of pentaerythritol mercaptocarboxylic acid ester, the use of an azeotropic agent is not an essential condition, but a method of removing the by-products continuously by heating under reflux using an azeotropic agent is generally carried out. As an azeotropic agent normally used, benzene, toluene, xylene, nitrobenzene, chlorobenzene, dichlorobenzene, anisole, diphenyl ether, methylene chloride, chloroform, dichloroethane, etc. are mentioned, for example. These may be used in mixture of 2 or more types, and may be used in mixture with another solvent.

The pentaerythritol mercaptocarboxylic acid ester of this embodiment obtained by the method mentioned above, the following compounds are mentioned, for example. Pentaerythritol thioglycolic acid ester, pentaerythritol 3-mercaptopropionic acid ester, pentaerythritol thiol lactate ester, pentaerythritol thiosalicylic acid ester, etc. are mentioned, but this invention is not limited to these exemplary compounds. In addition, these ester compounds may be a compound in which the hydroxyl group of pentaerythritol is fully esterified, or a compound in which only part of the ester is esterified. Moreover, you may mix 2 or more types of these ester compounds.

Moreover, the polymeric composition which concerns on embodiment of this invention is obtained from the pentaerythritol mercaptocarboxylic acid ester and polyiso (thio) cyanate compound mentioned above.

The polyiso (thio) cyanate compound used in the polymerizable composition of the present embodiment is a compound having at least two or more iso (thio) cyanate groups in one molecule, and is not particularly limited, but specifically, hexamethylene di Isocyanate, 2,2-dimethylpentane diisocyanate, 2,2,4-trimethylhexanediisocyanate, butene diisocyanate, 1,3-butadiene-1,4-diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate , 1,6,11-undecanetriisocyanate, 1,3,6-hexamethylenetriisocyanate, 1,8-diisocyanato-4-isocyanatomethyloctane, bis (isocyanatoethyl) carbonate Aliphatic polyisocyanate compounds such as bis (isocyanatoethyl) ether, lysine diisocyanatomethyl ester, and lysine triisocyanate;

1,2-diisocyanatobenzene, 1,3-diisocyanatobenzene, 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene, ethylphenylene diisocyanate, isopropylphenylene diisocyanate , Dimethylphenylene diisocyanate, diethylphenylene diisocyanate, diisopropylphenylene diisocyanate, trimethylbenzenetriisocyanate, benzenetriisocyanate, biphenyl diisocyanate, toluidine diisocyanate, 4,4'-methylenebis (phenyl isocyanate), 4 , 4'-methylenebis (2-methylphenylisocyanate), bibenzyl-4,4'-diisocyanate, bis (isocyanatophenyl) ethylene, bis (isocyanatoethyl) benzene, bis (isocyanato Propyl) benzene, α, α, α ', α'-tetramethylxylene diisocyanate, bis (isocyanatobutyl) benzene, bis (isocyanatomethyl) naphthalin, bis (isosia Ito phenyl) ether, bis (isocyanato ethyl) phthalate, 2,6-di (polyisocyanate compounds having an aromatic ring compound such as isocyanatomethyl) furan,

Bis (isocyanatomethyl) sulfide, bis (isocyanatoethyl) sulfide, bis (isocyanatopropyl) sulfide, bis (isocyanatohexyl) sulfide, bis (isocyanato Methyl) sulfone, bis (isocyanatomethyl) disulfide, bis (isocyanatoethyl) disulfide, bis (isocyanatopropyl) disulfide, bis (isocyanatomethylthio) methane, bis ( Isocyanatoethylthio) methane, bis (isocyanatomethylthio) ethane, bis (isocyanatoethylthio) ethane, 1,5-diisocyanato-2-isocyanatomethyl-3- Thiapentane, 1,2,3-tris (isocyanatomethylthio) propane, 1,2,3-tris (isocyanatoethylthio) propane, 3,5-dithia-1,2,6, 7-heptane tetraisocyanate, 2,6-diisocyanatomethyl-3,5-dithia-1,7-heptane diisocyanate, 2,5-diisocyanatomethylthiophene, 4-isocyanatoethyl Thio-2 Sulfur-containing aliphatic polyisocyanate compounds such as, 6-dithia-1,8-octane diisocyanate,

Aromatic sulfide-based polys such as 2-isocyanatophenyl-4-isocyanatophenyl sulfide, bis (4-isocyanatophenyl) sulfide, and bis (4-isocyanatomethylphenyl) sulfide Isocyanate compounds,

Bis (4-isocyanatophenyl) disulfide, bis (2-methyl-5-isocyanatophenyl) disulfide, bis (3-methyl-5-isocyanatophenyl) disulfide, bis (3 -Methyl-6-isocyanatophenyl) disulfide, bis (4-methyl-5-isocyanatophenyl) disulfide, bis (4-methoxy-3-isocyanatophenyl) disulfide, etc. Aromatic disulfide polyisocyanate compounds,

2,5-diisocyanatotetrahydrothiophene, 2,5-diisocyanatomethyltetrahydrothiophene, 3,4-diisocyanatomethyltetrahydrothiophene, 2,5-diisocyanato- 1,4-dithiane, 2,5-diisocyanatomethyl-1,4-dithiane, 4,5-diisocyanato-1,3-dithiorane, 4,5-bis (isocyanato Sulfur-containing alicyclic polyisocyanate compounds such as methyl) -1,3-dithiolane and 4,5-diisocyanatomethyl-2-methyl-1,3-dithiolane,

Alicyclic polyisothiocyanate compounds such as 1,2-diisothiocyanatoethane and 1,6-diisothiocyanatohexane, and cycloaliphatic polyisothiocyanate compounds such as cyclohexanediisothiocyanate, 1 , 2-diisothiocyanatobenzene, 1,3-diisothiocyanatobenzene, 1,4-diisothiocyanatobenzene, 2,4-diisothiocyanatotoluene, 2,5-diisothio Cyanato-m-xylene, 4,4'-methylenebis (phenylisothiocyanate), 4,4'-methylenebis (2-methylphenylisothiocyanate), 4,4'-methylenebis (3-methylphenyl Isothiocyanate), 4,4'-diisothiocyanatobenzophenone, 4,4'-diisothiocyanato-3,3'-dimethylbenzophenone, bis (4-isothiocyanatophenyl) ether Aromatic polyisothiocyanate compounds such as

Moreover, carbon, such as 1, 3- benzenedicarbonyl diisothiocyanate, 1, 4- benzenedicarbonyl diisothiocyanate, (2, 2-pyridine) -4, 4- dicarbonyl diisothiocyanate, etc. Sulfur-containing aliphatic isothiocia such as a carbonyl isothiocyanate compound, thiobis (3-isothiocyanatopropane), thiobis (2-isothiocyanatoethane), dithiobis (2-isothiocyanatoethane) Nate compound,

1-isothiocyanato-4-[(2-isothiocyanato) sulfonyl] benzene, thiobis (4-isothiocyanatobenzene), sulfonyl (4-isothiocyanatobenzene), dithiobis ( Sulfur-containing aromatic polyisothiocyanate compounds such as 4-isothiocyanatobenzene), 2,5-diisothiocyanatothiophene, 2,5-diisothiocyanato-1,4-dithiane and the like Sulfur-containing alicyclic compounds,

1-isocyanato-6-isothiocyanatohexane, 1-isocyanato-4-isothiocyanatocyclohexane, 1-isocyanato-4-isothiocyanatobenzene, 4-methyl- 3-isocyanato-1-isothiothiocyanatobenzene, 2-isocyanato-4,6-diisothiocyanato1,3,5-triazine, 4-isocyanatophenyl-4- Although compounds having isocyanate groups and isothiocyanate groups, such as isothiocyanatophenyl sulfide and 2-isocyanatoethyl-2-isothiocyanatoethyl disulfide, etc., are not limited to these exemplary compounds. .

Furthermore, halogen substituents such as chlorine substituents and bromine substituents, alkyl substituents, alkoxy substituents, prepolymer-type modified compounds with nitro substituents and polyhydric alcohols, carbodiimide modified products, urea modified products, biuret modified products, dimerized or trimmers The reaction product may also be used. These compounds may be used alone or in combination of two or more thereof.

The use ratio of pentaerythritol mercaptocarboxylic acid ester and a polyiso (thio) cyanate compound is usually in the range of SH group / NCO group = 0.3-2.0, Preferably it is in the range of 0.7-2.0.

In the polymerizable composition forming a urethane resin for the purpose of improving the physical properties, operability, polymerization reactivity, and the like required for the polyurethane-based resin of the present embodiment described later, in addition to the aforementioned ester and iso (thio) cyanate compound, You may add 1 type, or 2 or more types other than urethane formation raw materials, such as an active hydrogen compound, an epoxide compound, an olefin compound, a carbonate compound, an ester compound, a metal, a metal oxide, an organometallic compound, an inorganic substance, etc. represented by these.

According to the purpose, various substances such as chain extenders, crosslinking agents, light stabilizers, ultraviolet absorbers, antioxidants, oil-soluble dyes, fillers, mold release agents, and blue ink agents are added as in the known molding method. You may also In order to adjust to a desired reaction rate, thiocarbamic acid S-alkyl ester or the well-known reaction catalyst used in manufacture of a polyurethane can also be added suitably. The polyurethane-based resin of the present embodiment is usually obtained by casting polymerization.

Specifically, pentaerythritol mercaptocarboxylic acid ester and a polyiso (thio) cyanate compound are mixed. If necessary, after performing defoaming by a suitable method, this mixed liquid is injected into a mold, and is normally heated and polymerized gradually from low temperature to high temperature.

The polyurethane-based resin of the present embodiment thus obtained usually has high refractive index, low dispersion, excellent heat resistance and durability, light weight, excellent impact resistance, and the occurrence of turbidity due to the effect of the present invention. It is suppressed and is suitable as optical element materials, such as a spectacle lens and a camera lens.

Moreover, the optical element which concerns on embodiment of this invention is obtained from resin which concerns on embodiment mentioned above. As such an optical element, a lens is mentioned, for example. Such a lens is usually obtained by casting polymerization.

In addition, the polyurethane-based lens of the present embodiment has a surface for improving antireflection, high hardness, abrasion resistance, chemical resistance, weatherproofness, or fashionability, as necessary. Physical and chemical treatments such as polishing, antistatic treatment, hard coat treatment, anti-reflective coating treatment, dyeing treatment and light treatment can be performed.

[Example]

Hereinafter, the present invention will be described in detail with reference to examples. Analysis of the pentaerythritol used was performed by the following method. In addition, in the performance of obtained resin, refractive index, mold release property, foam | bubble, and transparency were evaluated by the following test methods.

Bispentaerythritol content: The pentaerythritol was dissolved in water and measured by high performance liquid chromatography.

• Content of sodium and calcium: After dissolving pentaerythritol in water, it measured by high performance liquid ion chromatography.

• Content of other metals: After pentaerythritol was sintered, acidified by hydrochloric acid, a solution diluted with pure water was measured by an inductively coupled plasma emission spectrometer.

Refractive index (ne), Abbe number (νe): It measured at 20 degreeC using the Pulfrisch refractometer (Pulfrich 屈折 計).

-Mold release evaluation: It evaluated using the convex shaping | molding mold created with the glass mold and tape of outer diameter 84mm, height 17mm, outer diameter 84mm, and height 11mm. 10 sets of each were inserted, and after completion | finish of superposition | polymerization, it cooled to room temperature and the case where there was no damage | damage or division | segmentation of a mold was made into AA and others BB.

-Bubble evaluation: The plastic lens was observed under the microscope of 100 times, and it was set as BB and the case where there existed bubbles inside was AA.

Transparency: The circular flat plate of thickness 9mm and (phi) 75mm was created, it measured with the shade image apparatus, and AA and 51 or more were made into BB in the case of 50 or less in C luminance.

Example 1

(Synthesis of pentaerythritol (3-mercaptopropionic acid) ester)

Purity 95.0% containing 4.7% by weight of bispentaerythritol and 0.1% by weight of sodium (only metal is sodium) in a 1 liter four-necked reaction flask equipped with a stirrer, a reflux cooling water separator, a nitrogen gas purge tube, and a thermometer. 143.0 parts by weight (1.0 mol) of pentaerythritol, 4.0 parts by weight of p-toluenesulfonic acid monohydrate, 172.0 parts by weight of toluene, and 440.3 parts by weight (4.15 mol) of 3-mercaptopropionic acid were added, and water produced by heating under reflux was added. The reaction was carried out for 5 hours (internal temperature 104 to 121 ° C) while continuously pulling out of the system, and cooled to room temperature. The amount of water extracted out of the system was 99.0% based on the theoretically generated water. The reaction solution was washed with base and washed with water to remove toluene and traces of water under reduced pressure, and then filtered to obtain 465.0 parts by weight of pentaerythritol-3-mercaptopropionic acid ester (hereinafter abbreviated as PEMP). APHA of the obtained PEMP was 10 and SHV was 7.81 eq / g.

(Manufacture of Plastic Lens)

87 parts by weight of m-xylylene diisocyanate, 0.01 parts by weight of dibutyltin dichloride, 0.18 parts by weight of Zerek UN (acidic phosphate ester), and 0.10 parts by weight of biosorb 583 (ultraviolet absorber) were mixed and dissolved at 20 ° C. . 113 weight part of obtained PEMPs were charged and mixed, and it was set as the mixing uniform liquid. After defoaming this homogeneous liquid at 600 Pa for 1 hour, it filtered by the 3 micrometer Teflon (trademark) filter, and injected into the mold mold which consists of a glass mold and a tape. This mold was charged into an oven, the temperature was gradually raised to 10 ° C to 120 ° C, and the polymerization was carried out for 18 hours. After the completion of the polymerization, the mold was taken out of the oven and released, thereby obtaining a resin. The obtained resin was annealed at 120 degreeC for 3 hours. The obtained resin was colorless and had high transparency, and had a refractive index (ne) of 1.600, Abbe's number (? E) of 35, releasability evaluation AA, bubble evaluation AA, and C luminance showing transparency, and corresponded to AA.

[Example 2]

Instead of pentaerythritol used in Example 1, pentaerythritol was prepared in the same manner as in Example 1, except that pentaerythritol having a purity of 95.5% containing 4.0% by weight of bispentaerythritol and 0.02% by weight of calcium powder (metal component only of calcium) was used. (3 mercaptopropionic acid) ester was synthesize | combined. Using the obtained pentaerythritol (3-mercaptopropionic acid) ester, the plastic lens was produced and evaluated similarly to Example 1. Table 1 shows the evaluation results of the obtained plastic lens.

[Example 3]

Pentaerythritol thioglycolic acid ester was synthesized in the same manner as in Example 1, except that 382.3 parts by weight (4.15 mol) of thioglycolic acid was used instead of 3-mercaptopropionic acid. Using the obtained pentaerythritol thioglycolic acid ester, the plastic lens was manufactured and evaluated similarly to Example 1. Table 1 shows the evaluation results of the obtained plastic lens.

Example 4

Instead of pentaerythritol used in Example 1, pentaerythritol was prepared in the same manner as in Example 1 except that pentaerythritol having a purity of 93.9% containing 5.5% by weight of bispentaerythritol and 0.2% by weight of sodium (metal component only of sodium) was used. (3-mercaptopropionic acid) ester was synthesize | combined. Using the obtained pentaerythritol (3-mercaptopropionic acid) ester, the plastic lens was produced and evaluated similarly to Example 1. Table 1 shows the evaluation results of the obtained plastic lens.

Comparative Example 1

Instead of pentaerythritol used in Example 1, pentaerythritol was prepared in the same manner as in Example 1 except that pentaerythritol having a purity of 89.8% containing 1.0% by weight of bispentaerythritol and 3.1% by weight of sodium (metal component only of sodium) was used. (3-mercaptopropionic acid) ester was synthesize | combined. Using the obtained pentaerythritol (3-mercaptopropionic acid) ester, the plastic lens was produced and evaluated similarly to Example 1. Table 1 shows the evaluation results of the obtained plastic lens.

[Comparative Example 2]

Instead of pentaerythritol used in Example 1, pentaerythritol was prepared in the same manner as in Example 1, except that pentaerythritol having a purity of 85.3% containing 5.5% by weight of bispentaerythritol and 3.1% by weight of sodium (metal component only of sodium) was used. (3-mercaptopropionic acid) ester was synthesize | combined. Using the obtained pentaerythritol (3-mercaptopropionic acid) ester, the plastic lens was produced and evaluated similarly to Example 1. Table 1 shows the evaluation results of the obtained plastic lens.

[Comparative Example 3]

Instead of pentaerythritol used in Example 1, pentaerythritol was prepared in the same manner as in Example 1 except that pentaerythritol having a purity of 84.4% containing 5.5% by weight of bispentaerythritol and 3.1% by weight of calcium powder (metal component only of calcium) was used. (3-mercaptopropionic acid) ester was synthesize | combined. Using the obtained pentaerythritol (3-mercaptopropionic acid) ester, the plastic lens was produced and evaluated similarly to Example 1. Table 1 shows the evaluation results of the obtained plastic lens.

[Comparative Example 4]

Instead of pentaerythritol used in Example 3, pentaerythritol was prepared in the same manner as in Example 3 except that pentaerythritol having a purity of 84.4% containing 5.5% by weight of bispentaerythritol and 3.1% by weight of calcium powder (metal component only of calcium) was used. Thioglycolic acid ester was synthesize | combined. Using the obtained pentaerythritol thioglycolic acid ester, the plastic lens was manufactured and evaluated similarly to Example 1. Table 1 shows the evaluation results of the obtained plastic lens.

Evaluation of plastic lenses Refractive index (ne) Abbe number (νe) Dysplasia Bubble evaluation Transparency
C luminance Example 1 1.600 36 AA AA AA Example 2 1.600 36 AA AA AA Example 3 1.610 35 AA AA AA Comparative Example 1.600 36 BB BB AA Comparative Example 1 1.600 36 AA AA BB Comparative Example 2 1.600 36 BB BB BB Comparative Example 3 1.600 36 BB BB BB Comparative Example 4 1.610 35 BB BB BB

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, A various aspect can be taken. Hereinafter, such an aspect is enumerated.

(1) A method for producing a pentaerythritol mercaptocarboxylic acid ester in which pentaerythritol having a content of sodium and calcium in total of 1.0% by weight or less and a content of bispentaerythritol of 5.0% by weight or less is reacted with mercaptocarboxylic acid. will be.

(2) The manufacturing method of pentaerythritol mercaptocarboxylic acid ester as described in (1) whose content of the alkali metal and alkaline-earth metal in the said pentaerythritol is 1.0 weight% or less in total.

(3) The contents of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn in the pentaerythritol are total. The manufacturing method of pentaerythritol mercaptocarboxylic acid ester of Claim (1) which is 1.0 weight% or less.

(4) Pentaerythritol mercaptocarboxylic acid ester obtained by the manufacturing method in any one of said (1)-(3).

(5) A polymerizable composition comprising the pentaerythritol mercaptocarboxylic acid ester according to item (4) and a polyiso (thio) cyanate compound. Here, "consisting of a pentaerythritol mercaptocarboxylic acid ester and a polyiso (thio) cyanate compound" means that a part of the said polymerizable composition consists of the said pentaerythritol mercaptocarboxylic acid ester and a polyiso (thio) cyanate compound. It is the meaning including both when it is and a part of the said polymeric composition consists of the said pentaerythritol mercaptocarboxylic acid ester and a polyiso (thio) cyanate compound.

(6) Resin obtained by hardening | curing the polymeric composition of said (5).

(7) An optical element comprising the resin according to the above (6).

(8) A lens comprising the resin according to the above (6).

According to the above (7) and (8), "consist of resin" means that the optical element or all of the lens is composed of the resin, and the optical element or a part of the lens is the resin. It is the intention to include both when it consists of.

Claims (16)

delete delete delete delete delete delete delete delete delete delete delete delete Treating pentaerythritol by an acid treatment or recrystallization method to reduce the total amount of one or both of Na and Ca contained in the pentaerythritol to 0.1 wt% or less;
A method for producing pentaerythritol mercaptocarboxylic acid ester, which has a reaction step of reacting the pentaerythritol treated in the above step with mercaptocarboxylic acid. delete The pentaerythritol of Claim 13 including the process of heat-processing pentaerythritol at 160 degreeC-200 degreeC, and reducing the quantity of bispentaerythritol contained in the said pentaerythritol to 5.0 weight% or less before the said reaction process. Method for producing mercaptocarboxylic acid ester. The method according to claim 13, further comprising hydrolyzing bispentaerythritol while refluxing the pentaerythritol under a nitrogen atmosphere before the reaction step, and reducing the amount of bispentaerythritol contained in the pentaerythritol to 5.0 wt% or less. Method for producing pentaerythritol mercaptocarboxylic acid ester.